The first part of the communication is just to establish the connection between the client and the server and to decide the cryptographic keys they will use, etc.

<img src="/img/deployment/https/https02.drawio.svg">

This interaction between the client and the server to establish the TLS connection is called the **TLS handshake**.

### TLS with SNI Extension { #tls-with-sni-extension }

{* ../../docs_src/header_param_models/tutorial002_an_py310.py hl[10] *}

Wenn ein Client versucht, einige **zusätzliche Header** zu senden, erhält er eine **Error-<abbr title="Response – Antwort: Daten, die der Server zum anfragenden Client zurücksendet">Response</abbr>**.

        Thread.sleep(1000)
        sendTestRequest(twitterRequest)
        Thread.sleep(1000)
        sendTestRequest(googleRequest)
        Thread.sleep(2000)
      }
    } finally {
      client.connectionPool.evictAll()
      client.dispatcher.executorService.shutdownNow()

      if (launch == CommandLine) {
        process?.destroyForcibly()
      }
    }
  }

  private fun sendTestRequest(request: Request) {

    await websocket.accept()
    await websocket.send_json(value)
    await websocket.close()


client = TestClient(app)


def test_value_extracting_by_http():
    response = client.get("/http")
    assert response.status_code == 200
    assert response.json() == 42


def test_value_extracting_by_ws():
    with client.websocket_connect("/ws") as websocket:

which [TLS versions](https://square.github.io/okhttp/4.x/okhttp/okhttp3/-tls-version/) and [cipher suites](https://square.github.io/okhttp/4.x/okhttp/okhttp3/-cipher-suite/) to offer. A client that wants to maximize connectivity would include obsolete TLS versions and weak-by-design cipher suites. A strict client that wants to maximize security would be limited to only the latest TLS version and strongest cipher suites.

Specific security vs. connectivity decisions are implemented by [Co...

@app.get("/product")
async def create_item(product: Product):
    return product


client = TestClient(app)


def test_get_with_body():
    body = {"name": "Foo", "description": "Some description", "price": 5.5}
    response = client.request("GET", "/product", json=body)
    assert response.json() == body


def test_openapi_schema():
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text

    },
}


def test_schema():
    response = client.get("/openapi.json")
    assert response.status_code == status.HTTP_200_OK
    actual_schema = response.json()
    assert actual_schema == schema
    assert (
        len(actual_schema["paths"]["/"]["get"]["parameters"]) == 1
    )  # primary goal of this test


def test_response():
    response = client.get("/", headers={"someheader": "hello"})

):
    return {"path": path, "query": query}


client = TestClient(app)


def test_get_parameters():
    response = client.get("/test_path", params={"repeated_alias": "test_query"})
    assert response.status_code == 200, response.text
    assert response.json() == {"path": "test_path", "query": "test_query"}


def test_openapi_schema():
    response = client.get("/openapi.json")

    importlib.reload(tutorial001_py39)

    client = TestClient(tutorial001_py39.app)
    return client


def test_disable_openapi(monkeypatch):
    monkeypatch.setenv("OPENAPI_URL", "")
    # Load the client after setting the env var
    client = get_client()
    response = client.get("/openapi.json")
    assert response.status_code == 404, response.text
    response = client.get("/docs")

{* ../../docs_src/request_form_models/tutorial002_an_py39.py hl[12] *}

Wenn ein Client versucht, einige zusätzliche Daten zu senden, erhält er eine **Error-<abbr title="Response – Antwort: Daten, die der Server zum anfragenden Client zurücksendet">Response</abbr>**.

Zum Beispiel, wenn der Client versucht, folgende Formularfelder zu senden:

* `username`: `Rick`
* `password`: `Portal Gun`